Electric mine lamp



Nov. 24, 1931.

J. G. DALOZ ELECTRIC MINE LAMP Filed Nov 2 Sheets-Sheet l NOV. 24, 1931. I J DALQZ 1,833,318

ELECTRIC MINE LAMP Filed Nov. 16, 1928 2 Sheets-Sheet ,2

nun-m J les 64.5fm D0102 L m/enfal" MMM Patented Nov. 24, 1931 J'ULES ensron nALoaor coumanvon'i, FRANGE ELECTRIC MINE LAME Application filed November 16,1928, Serial No. 319,785, and in Belgium July 27, 1928. i

The present invention relates to electric mine lamps of the type provided with a bulb operating inside a chamber containing gas under pressure.

One of the objects of the invention is to provide improved means for producing and maintaining gaseous pressure inside the pressure chamber.

Another object is to provide means for i opening the circuit feeding the lamp bulb as soon as the globe containing gas under pressure breaks.

A further object is to provide means for compensating losses of gasfrom the pressure chamber. I

A still further object is to provide means for indicating loss of pressure fluid'so as to Warn the miner that the lamp is about to be extinguished. 7

Additional objectswill appear in the course of the detailed description nowto be given with reference to the accompanying drawings, in which; r

Fig. 1 is an axial section through one illustrative embodiment of the invention showing the pressure chamber in charged position;

Fig. 2 shows a possible variant of the lamp supporting structure represented in Fig. 1;

Fig. 3 represents, in section, a second form of lamp assembly;

Figs. 4 and 5 are sections illustrating a third embodimentof the invention;

Fig. 6 is a detail showing a'possible variant of the structures represented in Figs. 3 to 5 Fig. 7 represents a special assembly adapted to be used in thespecial case where the pressure chamber is filled with a liquid instead of a gas. I r Referring to Fig. 1 of the drawings, there is shown a lamp assembly consisting of a globe a adapted to contain gas or a liquid under pressure,a battery casing 19 provided with a threaded portion b ,a battery c fitted with resiliently supported contacts d,a topcasing e formed with a flange 6 adapted to coact with globe a and a threaded portion e adapted'to engage with b ,'afrubber membrane f having its outer extremity stretched over flange a of globe a,a bulb 9 having its metallic portion g supported by the minor extremity of membrane 7 in contact with current terminals hereinbelow described,+- a lamp basecomprising an insulating plate 71. supported on threaded ring 2' in contact 1 with membrane 7, a central lamp terminal 7' connected to a first contact j ,and a peripheral lamp terminal Z urged upwardly by spring k which is in conductive relation with a sec- 0nd contact terminal k ,and finally a small metal ball n supported between slightly cupped surfaces formed on the bottom of g and on the top of j. v

The lamp is prepared for use in the following manner: An appropriate gas or liquidis first introduced into globe a; the interior portlon of membrane f is then stretched over base 9? oflamp g and the exterior portion over the mouth of globe a so as to cover both faces of flange a metallic skirt Z islthen inserted under membrane '7 and is followed by spring k and plate It together with the va rious structures supported by or inserted in, the latter; the assembly then occupies a positlon corresponding to that shown in Fig. 3; as plate It is raised upward, membrane 7 compresses the fluid inside globe a, so that when annular ring 71 is finally screwed into place, globe a contains fluid sealed hermetically therein under'pressure by a double packed jolnt composedof rigid elements 6 e and h and compressible element 7 covering opposite faces of flange 11 To light bulb g, itsufiices only to screw the battery assembly into place so that elements d contact with terminals 7' and k If globe Va, breaks or is broken, the

fluid under pressure "therein is released and spring is pushes upward on skirt Z'so as to move bulb 9 out of contact with central electrode j thusextinguishing the lamp. Since the opening of the lighting circuit'j, 9 occurs under membrane 7 there is no. danger of the spark so produced igniting mine gases in the vicinity. The function of ball 12 isto prevent the miner attempting to relight the lamp. It is to be noted that when'skirt Z is pushed upward, ball a is no longer held inposition bybulb g. Theslightest movement of element y will therefore cause ball n tofall off 7 of its perch thus leaving a gap between 9 and 7' which cannot be filled by manoeuvring either of these elements.

In theform of device illustrated in Figs. 3 to 5, the rubber membrane f shown in Fig. 1 is replaced by a similar element formed so that a portion thereof runs part-way up the inside of globe a, while a narrow flanged portion f fits under fia'nge a and issealed in position by an annular clip a compressed between elements a and h. In this form or membrane, the stretchingefiect 'on' the ex'ternal portion represented. in Fig. 1 as covering both faces of flange a is eliminated, and the life of the membrane greatly increased. The lamps shown in these figures dlfi'er otherwlse from the-one shown in .F 1g, lonlyin the form ofthe'safety device (equiva'lent ofball for preventing relighting of the lamp by the miner. I:n theforni of safety device shown in Fig. v3, elementy' ismade in the formof a :tubular shell split at; its lower end so as to present series of tongues j-bent slightly outward and contacting When globe a breaks, tube 7' islifted out of contact wit-hi by springk and tongues j spreadenough to prevent their-reentryinside 9' when attempts are made to lower 7' back into position. It is to be-noted that the .elevation of Z and is effected by the pressure ojf springjs .on a pin traversing both of these elements and that lis, here shown .as extending/upward so .as ;;to,einb:race metal portiong :of :bulb g. The safetydevicerepresentedin Figs. 4 and 5 consists of a movablestem triangular or ;other non-circular lower portion fitting through.asimilarly shapedorificeh and ,contacting with .a guided pedestalo urgedupward by alspringok The Iheadof stem jis rotatably supported .in an insulating element connected to skirt Z. When globe ca, breaks, skirt 'Z is projected Iupward "by spring 7c and stemj slides through orifice 7L Itis evident that :the miner will. findit difficult, ifnot im :possible, :to readjust the position-of stem j so that the proper angularrelation' with orifice maybe reestablished. Fig. '5 shows how stem may be guided back into .709 lby some authorized person other than-the miner. 1 Figs. 2 1and l6 showvariants of the: safety .devicesfillustrated 1. and-3 to 5 respectively, Inthe structure represented. in

'2, ball at (Fig.1) is replaced by an assem lyl cn i s fee nsl 'at ne e' having an orifice therethrough permitting contact between and g, and afs'pring. m

supported on skirt 1. When globe at breaks and skirt Zmoves upward, spring m moves disc. m so that the orifice throughthelatter is I out of line with element j and the miner is therefore unable to reestablish the contact 9, y. In the device shown inFig. 6, a central movable electrode mounted to follow the movements of skirt -Z in the mannerofthe lstructures illustrated in Figs. 3;to '5, receives contact g in under the latter so that insulat ing surface 9 comes under said stem and prevents the conductive relation between andj tobereestablished, This'form of de vice is designed to be built into plates h, a

screw in line with spring 9 permitting'the "latter to be retracted-so as to move j back into operative position.

The variant shown in Fig. 7 is designed forthe special case in which. globe a is filled with water or some other electrically conducting liquid. The lamp assembly here'remains thev same as that shown. in Figs. 1 or 31cc 5 but, .inorder to preventdeterioration of rub.- ber membrane 7 by electrolysiswhich nor- ,mally would take place, specially,.at F, as:

Element gi -and also skirt Zare.thus in-v sulated from .the. pressureliquid and electrolytic effects which might otherwise be pro duced,,are entirely eliminated. 3

. The principal b 'ect of the presentinvention being to avoid the necessity of pumps' and other auxiliaries fiorintroducing and maintaining a gas under pressure inglobea, it will at once be'evident, thatthehereinabove described structures attain this object in 1a simple and practical manner.

It is tobe understood, of course,that-.certain details of. construction are not limited to the particular form of lamp structure illustrated in any one figurefv Thus, skirt Z may either'e tend-up to element gflas inj'Fig. 1, or embrace the latter as in Figs, 3 -to'5 and 7 the safetydevices shown inFigs, 1, 2, 3, .6 or i and 5 may be used interchangeably with theiorms of base .71, and skirt Z illustrated in other of the figures, it'bein-g obvious that persons skilled in the art will at once beable to regroup and modify the various cooperating elements tosobtain a workable combination. Finally, it is to be understoodthat the -various safety devices .equiva-lentto ball n in Fig. l constitute an optionalpand not a necessary, partfof the lamp assembly and may, if desired, beeliminated entirely, Thus, in Fig. 1,?ball may be left outaan'd central electrodej extended so asto contact directly with the central contact of bulb vg. V It has been found practicable to intro- -duce volatile substances of the natureof chloroform into globe a to. compensatefor any losses occurring through the joints.v

In thecourse of the use of the lamp, skirt Z may rise gradually, because of leakage losses, and finally extinguishthelamp To warn the miner ofzsuch an eventualityglobeqmay be engraved or marked at a point indicating the level above whichthe tip (or the base) of bulb 9 must not rise.

What I claim is 1. In electric lamps containing an electric bulb adapted to operate in a fluid under pressure, a fluid pressure producing assembly comprising a vitreous globe, a flexible membrane, a closure element for said globe, and means operative to force said membrane away from said closure and towards said globe when said closure is moved into operative position, said means having portions thereof lying in contact with the membrane and being displaceable both with relation to said globe and to said closure element.

2. In an electric lamp, a. Vitreous globe having a compressed fluid medium therein, an electric bulb provided with external metallic terminals and adapted to be inserted into said globe, a flexible membrane supported on said rigid element, and having its outer periphery formed to coact with the open end of the vitreous globe, a closure element formed to seal the open end of the vitreous globe, a rigid element shaped to contact electrically with one of the metallic termi nals of said bulb, said rigid element being independent of, and displaceable with relation to said closure element and said globe, a conductor positioned to conduct current to one of the metallic terminals of the electric bulb, contacts positioned on the exterior side of the closure element and in conductive relation with the conductor and the rigid ele ment, and means for supplying current to I said contacts.

3. An apparatus as defined in claim 2 in combination with resilient means interposed between the rigid element and the closure and tending to force the former away from the latter.

4. An apparatus as defined in claim 2 in combination with resilient means interposed between the rigid and the closure elements tending to separate these latter, and a spherical electrical conductor interposed between the said conductor and the cooperating bulb terminal held in position by the fluid pressure in said globe.

5. An apparatus as defined in claim 1 in combination with means for'conducting current to said bulb, and comprising a spherical electrical conductor held in position by the fluid pressure in said globe. V

In testimony whereof I have signed this specification.

J ULES GASTON DALOZ. 

